The coat of arms was designed by the College of Arms, and every element represents something personal to the Middleton family.

Three acorns, symbolising the Middleton children and the oak trees that grow near their family home in Bucklebury, Berkshire, are at the centre of the design.

In keeping with the tradition of including puns in official coats of arms, a thick gold band is featured, which signifies Carole Middleton's maiden name Goldsmith. Two white chevrons placed on either side of the band are designed to look like hills and mountains, representing the family's love of the outdoors.

A blue ribbon at the top of the crest signifies that Kate is an unmarried woman.

The garter king of arms at the College of Arms, Thomas Woodcock, designed the crest, but says he had lots of help from the Middleton family.

"They took enormous interest in this design," Woodcock told the UK's Daily Mail. "And, while its purpose is to provide a traditional heraldic identity for Catherine as she marries into the royal family, the intent was to represent the whole family together, their home and aspects of what they enjoy."

Kate is believed to be thrilled with her new crest, but she won't be able to use it for long. As soon as she marries William next week the Middleton coat of arms will be merged with his to create a new crest. This process is expected to take several months.